In this report, we analyzed the GHG emissions in Redwood City. We analyzed energy consumption data from 2013 to 2019 in terms of building emissions and vehicle emissions. Based on data from previous years, GHG emissions are forecast from 2020 to 2050.
For vehicle emissions, we used LODES 2013 to 2019 data to calculate commute emissions in Redwood City as both an origin and destination.
To get the geographical scope of the study, we first use zctas() to get the geographic information of each zip code area, and then use places() to filter to the boundary of redwood city. If the centroid of a zip code area is within the Redwood City boundary, then this zip code area will be regarded as a sub-region within the Redwood City. By calculation, we obtained three sub-regions within Redwood City: 94061, 04063, 94065. These three areas will serve as the entire geographical scope of the Redwood City.
In order to obtain the route of CBG - to ZIP level, for these three zip code areas (94061, 04063, 94065), we created a dataframe to save the block and CBG information corresponding to each zip code area.
| GEOID10 | cbg | zipcode |
|---|---|---|
| 060816107002010 | 060816107002 | 94061 |
| 060816108002006 | 060816108002 | 94061 |
| 060816107002004 | 060816107002 | 94061 |
| 060816110004017 | 060816110004 | 94061 |
| 060816107002002 | 060816107002 | 94061 |
After we got LODES data, we filtered out routes that origin and destination are within Redwood City blocks. We assumed that these short commutes would not have a significant impact on the total vehicle emissions. In this way, routes could be divided into two categories, the first category “inbound”, that is, from the outside of Redwood City to a destination within the boundary; the second category “inbound”, that is, from Redwood City to an external destination.
Next, we did a transformation on all routes. To be specific, whether the route is outbound or inbound, the endpoint within the Redwood City would be assigned to a location that was the same as the centroid of the zip code area; the endpoint outside the Redwood City would be assigned to a location that was the same as the centroid of the CBG area.
After the above-mentioned series of processes and transformations, we used mb_directions to obtain all the routes details. We created a dataframe to store the distance, duration and geographic information of each route. So far, we got the distance of each route, and the distance could be used to calculate VMT. VTM are important indicator of GHG emissions, so that we can convert vehicle miles to emissions. The map below shows all the routes from or to Redwood City.